Thanks Pavlina,
I need to call this function on the GridButtonColumn's button click and not when the row is selected.
Are there any client side events for this column?
My Senario:
I have a grid with one of the columns as GridButtonColumn 'Show Map'. When this ShowMap button is clicked I need to access 'Address' field of that row and pass it as parameter to the Radwindow and show it as a model.